Selective ringing-key.



B. W. SWEET.

SELECTIVE RINGING KEY. APPLICATION FILED SEPT. 28, 1906.

947,722. Patented Jan.25, 1910.

E v I UNITED STATES PATENT OFFICE.

BURTON W. SWEET, OF CLEVELAND, OHIO, 'ASSIGNOR,'BY MESNE ASSIGNMENTS, TO

CENTURY TELEPHONE CONSTRUCTION COMPANY, OF BUFFALO, NEW YORK, A.

CORPORATION OF NEW YORK SELECTIVE RINGING-KEY.

Specification of Letters Patent. Patented Jan. 25, 1910, Application filed September 28, 1906. Serial No. 336,586.

To all whom it may concern:

Be it known that I, BURTON IV. Swrmr,a citizen of the United States of America, and a resident .of Cleveland, in the county of Cuyahoga and State of Ohio, have invented certain new and useful Improvements 'in Selective Ringing-Keys, ofwhich the following is a specification.

My inventionrelates to improvements in selective ringing-keys adapted for use in connection with telephone party lines; the same bein connected in the cord circuit at the central-office or exchange, and associated with suitable selective currents to be alternatively thrown out upon the line and ring the signahbell corresponding to such current.

.The object of my improvement has been to simplify and ,cheapen this type of a'p'- pliance, and to produce at the same time,

astructure which shall be thoroughly efficient and durable.

The embodiment of 'my invention presents aringing-key which combines the aforesaid advantages, and contains but few parts, which are readily assembled to form the complete device.

Briefly describing this ringing-key of my invention in a preliminary way, Inlay say that the circuit-changing apparatus com prises a plurality of vertically-mounted contact-springs adapted to be alternatively actuated by corresponding plungers. A simple slide-bar normally retains the plunger last depressed. to indicate the party which was rung; said bar being controlled by a light spring, and affording practically no resistance 'to the depression of the plungers.

Upon each plunger is an integral collar and detent-member, carrying upon one side the actuating roller for the contact springs, and upon the other, the pin or stop engaging the slide-bar. A. UIllVOl'Stll retaining-member holds said rollers in place, and at the same time prevents the plungers from twisting or turning, whereby the slide-bar is actuated with certainty and ease. These, and other features of advantage will be a )parent upon referring to the appended drawing illustrating the selective inging-key of my improveirient adapted fori'inging four-party lines, and associated with a master-key adapted for individual ringing, and for simultaneously releasing any depressed plungen In said drawing, Figure I. is a side elevation of the complete selective ringing and master-key appliance. Fig.- II. is a vertical sectioir through one of the selective ringing members; and, Fig. III. is a fragmentary side elevation, showing the device from the side opposite that depicted in Fig. I.

The same character of reference has been employed throughout, to indicate similar parts.

The

- v face-plate a serves to mount the several parts of the key. Posts "6 associated after complete depression engaging its insulating roller 0, with the two flaring actuated-springs, and having moved them intd contactwit-h the outer or line springs of the corres 'onding set (Z, to send a selective si nal. T is plungerv is thus held by means 0 the slotted and recessed slide-bar f, which is held in place by means of two screws f entering the posts 6, and actuated by a twisted leaf-spring f upon the left-hand post. At the other end of said slide-bar is a roller f of insulating material, engaging an upright spring of the set fl belonging to the master-key upon the right. The collar 1 secured upon each of the plungers, as best shown in Fig. II, has outwardly extending integral pins g 9 respectively engaging the slide-bar f, and carrying the msulatingroller e, and also engaging the slotted retaining-member h. A coiled spring 2' upon each of the plungers opposes the downward movement.- thereof.

The construction of the individual or master-key upon the right conforms to the Well known oscillating type of ringing and listening-key; the lever Z thereof carrying an insulating roller is, which is adapted to oscillate between the two uppermost of the set of contact springs d. When said lever l is thrown either from .the listening-1n or the median position in which it is shown,

releasing any lungerw ich has previously been depresse Those conversant with telephone practice a will understand that this construction is one which cancels the indication of the party which was last selectively rung. Thus, if plungers 1, 3 or 4; had been previously depressed, that plunger would be held in its semi-depressed position, and plunger 2,. on the contrary, would be released from the position shown. This always furnishes a certain indication as to which party is the one desired and may r uire a repeated or additional signal to will himv to the telephone.

Having given above brief attention to the well known functions of'this appliance, I may now point out that the'stru'cture illustrated is one which is unusua'll rigid and durable, andcontains relative y few and simple parts... Thus, the plun ers are all retained iii-preper position, an their insu lating rollersere held in place by the L shaped strip forming retaining-member h WlllCl'l is screwed beneath plate a, after the parts have been assembled with its slots closely embracing the pins 9 v The slideebar f is of simple construction, and accommodates the pins g within the recesses f, or temporarily retains the depressed .pm by means of the outer-cut point 7, asfshown in Fi I.

I -lavingnoiv described and shown themeferred embodiment of my invention, I claim as new, and desire to secure by Letters Patent, the following 1. In a selective ringing-key, the com bi nation with a plurality of plungers and associated sets of contact-springs adapted to be individually actuated thereby, of transversely extending deteiits respectively provided upon said plungers, a universal slidebar equipped with angularly disposed recesses and under-cut points associated with said detents, a light spring op osing the longitudinal movement of said ar, and a slotted member accommodating the, detents to prevent rotation of the plunger and insure the actuation of the slide-bar, substantially as and for the purpose set forth.

2. In a selective ringing-key, the combination with a plurality of plungers and assoindividually actuated thereby, of transve'rsely extending cletents respectively provided upon said plungers, a universal slide bar equipped with angular-1y disposed re cesses and under-cut points associated with saiddetents, a light spring 0 posing the longitudinal movement of said ar, insulat .ing parts carried by saiddetents respectively adapted to actuate the contact-springs, and a slotted retaining-member engaged by said detentsj the same being positioned to retain the insulating parts in place and insure the vertical movement of the plungers, substantially as set forth.

3.- In an operators selective rin ing-key, the combination with a plurality o reciprocating plungers, of, sets 6f contact-springs res ectively controlled thereby, a recessed slide-bar mounted at one side to have longitudinal movement, integral detent nembers provided upon each of the plungers and hating'pins extending upon either side respectively to on age the recessed slide-bar and a vertically s otted' member, insulating parts carried upon said pins opposite the slide-bar, and a vertically slotted retaining member engaging said pins-beyondsaid insulating parts, and ada tedto secure them in their assembled relations and prevent the turning of. the plungers, substantially as set forth.

4. In an o rators selective ringing-key,

the combination with a plurality of red rocating plungers, of sets of contactsprings res ectivelycontrolled thereby, a recessed sli e=bar mounted at one side to have longitudinal movement, integral detent-members provided upon each of the plungers and hav ing pins extending upon-either side respee tively to engage the rece's'sedslide bar and a vertically slotted member, insulating parts carried u on said ins opposite the slide-bar, a vertica ly slotted retainin member engaging said pins beyond said insulating parts, and adapted to secure them in their assembled relations and prevent the turning of the plung'ers, and an oscillating ringing-key associated with the slide-bar and positioned to impart longitudinal movement thereto in the act of ring1n'g,-whereby the plungers are released, substantially as set forth.

Executed by me at Cleveland, this twentyseventh day of September, A. D. 1906, before the undersigned witnesses.

. BURTON w. swam.

Vitnesses V. G. ARMSTRONG,

ciated sets of contact-springs adapted to be ALBERT LYNN LAWRENCE. 

